Commit b722c82c by Joseph Myers Committed by Joseph Myers

* extend.texi: Update documentation for default format attributes.

From-SVN: r37844
parent 01fa3508
2000-11-29 Joseph S. Myers <jsm28@cam.ac.uk>
* extend.texi: Update documentation for default format attributes.
Tue Nov 28 21:56:45 2000 Jeffrey A Law (law@cygnus.com)
* pa/pa-64.h (ASM_OUTPUT_SECTION_NAME): Use a hash table, not
......
......@@ -1525,7 +1525,8 @@ string argument (starting from 1), while @var{first-to-check} is the
number of the first argument to check against the format string. For
functions where the arguments are not available to be checked (such as
@code{vprintf}), specify the third parameter as zero. In this case the
compiler only checks the format string for consistency.
compiler only checks the format string for consistency. For
@code{strftime} formats, the third parameter is required to be zero.
In the example above, the format string (@code{my_format}) is the second
argument of the function @code{my_print}, and the arguments to check
......@@ -1534,12 +1535,16 @@ attribute are 2 and 3.
The @code{format} attribute allows you to identify your own functions
which take format strings as arguments, so that GNU CC can check the
calls to these functions for errors. The compiler always checks formats
for the ANSI library functions @code{printf}, @code{fprintf},
calls to these functions for errors. The compiler always (unless
@samp{-ffreestanding} is used) checks formats
for the standard library functions @code{printf}, @code{fprintf},
@code{sprintf}, @code{scanf}, @code{fscanf}, @code{sscanf}, @code{strftime},
@code{vprintf}, @code{vfprintf} and @code{vsprintf} whenever such
warnings are requested (using @samp{-Wformat}), so there is no need to
modify the header file @file{stdio.h}.
modify the header file @file{stdio.h}. In C99 mode, the functions
@code{snprintf}, @code{vsnprintf}, @code{vscanf}, @code{vfscanf} and
@code{vsscanf} are also checked.
@xref{C Dialect Options,,Options Controlling C Dialect}.
@item format_arg (@var{string-index})
@cindex @code{format_arg} function attribute
......@@ -1568,7 +1573,9 @@ functions which modify format strings, so that GNU CC can check the
calls to @code{printf}, @code{scanf}, or @code{strftime} function whose
operands are a call to one of your own function. The compiler always
treats @code{gettext}, @code{dgettext}, and @code{dcgettext} in this
manner.
manner except when strict ISO C support is requested by @samp{-ansi} or
an appropriate @samp{-std} option, or @samp{-ffreestanding} is used.
@xref{C Dialect Options,,Options Controlling C Dialect}.
@item no_instrument_function
@cindex @code{no_instrument_function} function attribute
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment